Upgrading to DreamHost Private Servers
DreamHost PS gives you your own "virtual machine", protecting your CPU and RAM on your physical machine for faster websites. Here's what I like and dislike about DreamHostPS, and some of the issues and solutions for migrating.
DNS Round Robin Configuration using Rsync over SSH
The goal is to add the HostGator server to be an exact mirror of the s.askapache.net domain, then to add that server as a 2nd A record to my DNS zone. That way half the visitors to the size will be taking up resources and bandwidth on the HostGator server instead of mine.
Round Robin A records in DNS are intended to evenly distribute queries between each host of the same name. Using some tricks straight out of a hackers toolbox we can verify if the distribution is taking place. (It is.)
Optimizing Servers and Processes for Speed with ionice, nice, ulimit
To prepare for several upcoming articles on AskApache that are focused on optimizing Servers and Sites from a server admin level, here is an article to introduce the main tools that we will be using. These tools are used to optimize CPU time for each process using nice and renice, and other tools like ionice are used to optimize the Disk IO, or Disk speed / Disk traffic for each process. Then you can make sure your mysqld and httpd processes are always fast and prioritized.
ListOfErrors
DreamHost’s Private Servers Finally Rooted
Web Development Glossary
THE Ultimate Htaccess
.htaccess is a very ancient configuration file for web servers, and is one of the most powerful configuration files most webmasters will ever come across. This htaccess guide shows off the very best of the best htaccess tricks and code snippets from hackers and server administrators.
You've come to the right place if you are looking to acquire mad skills for using .htaccess files!
Running a Reverse Proxy in Apache
Apache Web Server Speed Configuration Hacks
Apache server performance can be improved by adding additional hardware resources such as RAM, faster CPU, etc.COMPUTER SECURITY TOOLBOX
List of mainly obscure security software geared more for the master pentester. These are mostly for unix, bsd, and mac and many are difficult to install and setup (require custom servers, inside access points, obscure libraries). Only programs that output data are included, so no actual exploits or anything. Most of these output extremely useful albeit extremely technical information.Caching Tutorial for Webmasters
If you examine the preferences dialog of any modern Web browser (like Internet Explorer, Safari or Mozilla), you'll probably notice a 'cache' setting. This lets you set aside a section of your computer's hard disk to store representations that you've seen, just for you. The browser cache works according to fairly simple rules. It will check to make sure that the representations are fresh, usually once a session (that is, the once in the current invocation of the browser).
An AskApache Plugin Upgrade to Rule them All
So my blog as been rather quiet for almost a year now, and very few updates if any have been released for my Password Protection PLugin, my Google 404 Plugin, and definately not for my AskApache CrazyCache plugin, which I will be releasing last... So for all of you who've helped me out by sending me suggestions and notifying me of errors and sticking with it... Just wanted to say sorry about that, and thanks for all the great ideas.. Well, I've been sticking with it as well believe it our not. I manage to get free days once in a while, and then its time to jam.
IP Blocked by stateful Firewall, now what?
FastCGI on DreamHost
Using FastCGI on DreamHost and .htaccess
Apache Directives and Modules on DreamHost
Apache .htaccess Directives and Loaded Modules allowed on DreamHost Apache Server 2 Setups.
Free DNS Services
Password Protection Plugin Status
Enumerating Permissions can be Annoying
Don’t ask me how because I won’t tell you, but on one of the hosts I was testing on that did not allow direct access I was able to get the Apache server running as dhapache to erroneously write a file into my users blog directory. This is a big security no-no and I now have my .htaccess file written into the blog directory where it should go, but instead of my php script’s user having write access to the file so I can modify it, its owned by dhapache! Because the file is owned by dhapache I shouldn’t even be allowed to know it exists, but there it is. So the next step was to try and take ownership of the .htaccess file so that I could modify it. I tried and tried but was unsuccessful, I couldn’t modify it so that was another dead end. Actually it took me awhile to figure out how to remove the file from my directory. Being that it was owned by dhapache I couldn’t delete or modify it using my php process or even through ftp/ssh! Sysadmins regularly run find commands that search the servers for any files owned by dhapache that should not be there as this is a big red flag that someone has found a way to manipulate dhapache which could potentially lead to modifying dhapache-owned server config files, which sometimes is all it takes to hack your website and server.. Luckily I was able to delete it by basically running the hack again to overwrite the file.
Caching WordPress with Batcache and Memcache
Using memcache for me personally and the client sites I work on, has improved performance by over 1000%, in some cases even higher than that. It is a truly revolutionary way to optimize the performance of MySQL queries, remote requests such as to twitter or other apis, and this article is step 1. Plan is to go all the way to step 10 in future articles, it it grossly underused and misused in the WP world.
Faster DNS Lookups
Apache 2.4 and PHP-FPM
PortaPutty Auto-Reconnecting SSH Tunnels on an Encrypted TrueCrypt Portable USB Key w GPG
Ok I just came back up to write the intro.. I'm trying to keep it short to avoid getting bogged down by the coolness of each step. Here is what goes on. When I logon to my XP machine at work, I bring my usb key and plug it in first. On logging a window pops up first and it's a password prompt to mount my encrypted drive leonardo. It also checks a keyfile that is located on my usb key, but all I do now is type in my password. That causes my encrypted folder to be accessible to me like a normal drive, and it autoruns a startup batch file.
The batch file causes Portable versions of Firefox (all my bookmarks, my settings) to load, and launches Portable Mozilla Thunderbird (IMAP makes this work well), which is my favorite program (great GPG features and open-source!). Also Some Adobe CS4 software is loaded from the hard drive, like DreamWeaver. In the background, a service we created executes a PortaPuttY plink command to create forwarded tunnels from various remote servers and accounts, all using key-based encryption. These tunnels are automatically reconnected if they are disconnected, meaning you can use a socks 5 if you want or even better!
View all MySQL Variables for Pasting into my.cnf
This is really useful for me because I work with dozens of different database servers. The first thing I do is run this command and paste it into the servers /etc/my.cnf file. That way I will always know the original value and it just makes life much easier.
$ mysql -NBe 'SHOW VARIABLES' |sed 's,\t,^=,'|column -ts^|tr "\n" '@'|eval $(echo "sed '" "s,@\("{a..z}"\),\n\n\1,;" "'")|tr '@' "\n"|sed 's,^,# ,g'
About AskApache
Internet Census 2012 – Port scanning using insecure embedded devices – Carna Botnet
While playing around with the Nmap Scripting Engine (NSE) we discovered an amazing number of open embedded devices on the Internet. Many of them are based on Linux and allow login to standard BusyBox with empty or default credentials. We used these devices to build a distributed port scanner to scan all IPv4 addresses. These scans include service probes for the most common ports, ICMP ping, reverse DNS and SYN scans. We analyzed some of the data to get an estimation of the IP address usage.
Mod_Status tricks to View Apache Module Directives
Quick and easy method to get a list of all Apache Modules currently loaded, a list of all the directives each module provides, a list of currently used directives, etc... These directives can be used in httpd.conf and/or .htaccess files so it is definately useful to know which ones are available and which ones are currently being used.
Vetted – Top 3 WordPress Speed Plugins
There are so many WordPress plugins out there now that I wanted to post my favorite 3 plugins for speeding up a WP-Powered blog. These are the 3 plugins that I install for pretty much all of my WP-Powered sites, which I run about 300 now. They work together to provide a very optimized blog for speed.
DB-Cache Reloaded does something entirely different, it saves the mysql queries that are made to the WP-database, as well as the mysql results to static files, and then through php serves those cached-files instead of re-querying the mysql database. Most mysql databases are stored on separate servers, and although many are on the same local network there is a limit to how many queries, and how many connections can take place.
So DB-Cache Reloaded basically makes WP-Super Cache work alot faster when generating the cache files, and DB-Cache Reloaded helps in a number of areas un-related to WP-Super Cache, like in the admin panel. And DB-Cache without WP-Super-Cache is a joke because it still uses the application-level and php for everything. Gotta use both (or just WPSC).
30x Faster Cache and Site Speed with TMPFS
NOT a typo.. 30x is measurable, well-documented, and easily tested. This is what open-source is about. I haven’t had time to post much the past year, I'm always working! So I wanted to make up for that by publishing an article on a topic that would blow your mind and be something that you could actually start using and really get some benefit out of it. This is one of those articles that the majority of web hosting companies would love to see in paperback, so they could burn it.
HOWTO: Uninstall CPANEL over SSH
The following is just a quick but detailed reference of some of the commands I used to successfully uninstall cpanel permanently. This is for advanced users of the shell. If you run a single one of these commands without fully understanding it, you will probably kill your server, lose everything on it permanently, not have a website or email for weeks.. So backup everything. FIRST. You should also contact your hosting provider support - but be prepared for some MAJOR negativity.. cpanel makes things very easy for web-hosting companies, and you are less than a drop in their bucket.
SPF Records on DreamHost
Here are the steps that I take to get an SPF Record going on DreamHost
v=spf1 mx ip4:64.111.100.0/24 ip4:66.33.201.0/24 ip4:66.33.216.0/24 ip4:208.97.1 32.0/24 ip4:208.97.187.0/24 ip4:208.113.200.0/24 ip4:208.113.244.0/24 ip4:64.18.0.0/20 ip4:74.125.148.0/22 include:aspmx.googlemail.com include:_spf.google.com ~all
DreamHost Server IP Address List
A list of all DreamHost Servers and corresponding IP address. The dreamhost.com DNS zone is currently having troubles, so most hostnames within this zone are not resolving.Questions I Ask Web Hosting Companies, Before Buying
The following is a transcript of a chat I had with a company called tektonic, and at that time I was looking for a cheap linux host to use for some redundancy/failover operations. I generally contact a new hosting company like this every few months.. I like to have options available in case of some kind of failure or network attack, so it's always a good idea to have a few ace linux servers in your back pocket.
If you've read any other articles on AskApache, you can see a certain obsession towards optimization, speed, and security -- so that is the purpose of the following questions.
Dealing with Mobile Visitors using Bad Browsers
Notes from Apache HTTPD Source Code
thought I'd take a break from coding and post about how open-source is such a great tool for finding the best answers to the toughest questions,
/** is the status code informational */ #define ap_is_HTTP_INFO(x) (((x) >= 100)&&((x) < 200)) /** is the status code OK ?*/ #define ap_is_HTTP_SUCCESS(x) (((x) >= 200)&&((x) < 300)) /** is the status code a redirect */ #define ap_is_HTTP_REDIRECT(x) (((x) >= 300)&&((x) < 400)) /** is the status code a error (client or server) */ #define ap_is_HTTP_ERROR(x) (((x) >= 400)&&((x) < 600)) /** is the status code a client error */ #define ap_is_HTTP_CLIENT_ERROR(x) (((x) >= 400)&&((x) < 500)) /** is the status code a server error */ #define ap_is_HTTP_SERVER_ERROR(x) (((x) >= 500)&&((x) < 600)) /** is the status code a (potentially) valid response code? */ #define ap_is_HTTP_VALID_RESPONSE(x) (((x) >= 100)&&((x) < 600))
Htaccess SEO Trends by Google
htaccess vs. httpd.conf
Custom PHP.ini tips and tricks
- When php run as Apache Module (mod_php)
- When php run as CGI
- When cgi?d php is run with wrapper (for FastCGI)
If you can crash your daemon, you likely have a security problem
Tons of awesome tips and tricks using netcat. Port redirector, nessus wrapper, capture exploits being sent by vuln scanners, etc. This is very useful for doing stuff like redirecting traffic through your firewall out to other places like web servers and mail hubs, while posing no risk to the firewall machine itself.
Better, Faster, Stronger gethostbyaddr
Debugging Tools for Windows
I am almost ready to publish the final tutorial on using ssh tunnels from a truecrypt partition on a Windows machine. Of course I choose to go way overboard in my research and the tutorial is full of some pretty awesome windows tricks.. I will come back to this post soon and post all the other advanced tools I use for debugging windows, for now though you MUST know how to debug the kernel and use these basic debugging tools.
Using PHP shorthand and short_open_tag
I hope this will pursuade you to stop using PHP short_open_tag syntax.<?= or <?